Thermostat placement in new server room

I'd highly recommend you also speak with the HVAC tech who is setting up your AC as well.

I put one in each rack.

Sometimes Venting will not be adequate to remove heat from the racks. So, your servers overheat. This is why I put one in each rack.

The HVAC/installer wants to place the thermostat on the wall when you first walk through the door on the left. It would be in the location of the spot cooler in the drawing.

ChiefIT does having one in each rack require any special setup?

In this case not much diffrent, where you are going to put termostat(any reasonable distance away from grills)- most important, have air circulation within the racks(add spacing, and additional fans for hot spots inside the rack).
If you want to be more protected- you can use SNMP monitoring- like  www.solarwinds.com see exact tempature of CPU/ and so on of most of hardware you have(SNMP can send you alarms , if if tempeture exceed normal )- this way you will independent from  HVAC monitoring and prevention, as well increasing redundancy(do not depend on "single point of failure").
For other automation purposes you can use - www.amx.com hardware  - it does have a lot integrated simplicity for serial/touch panel control option.

Usually, they are just serial sensors that hook up to a computer and have an application that will send an email if the temp gets too hot within the cabinet. They are plugged into a PC, the application spits out data.

I'll tell you what, Visit this web site and check out the NOAAS Oscar Sette. I have all kinds of Serial sensors that provide WIND direction, Wind speed, Air temp, Barometric readings. GPS location, Water temp. Ect...... This data is all serial sensor data that is collected and sent out to a shore station via email.

http://www.sailwx.info/shiptrack/researchships.phtml

"Serial sensonrs" needs to be attached to equipment, when SNMP monitoring does acquare information using SNMP protocol, have whole picture, more beyond just tempature.

I know about temp sensors and monitors, what I was referring to is the wall control thermostat that controls the main ac unit. Would this need to be mounted in the rack or would it stay on the wall where they want to put it and if so is that location a good location?

Thank you everyone for participation.

Also when you can, make sure the door to the server room is closed.  Typically server rooms are/should be cooler than standard ambient around the rest of the office, and having the door open will make the AC work harder unnecessarily.

The HVAC tech's suggestion is pretty much consistent with what I was thinking of a good location.  Just make sure not to stack too much stuff around it if you intend to use that wall for boxes/towers/equipment.